1. Field of the Invention
The present invention relates to a rocker switch for an electronic device and more particularly to a four-way rocker switch having a display mounted thereon for use in a cell phone.
2. Discussion of the Background
In order to miniaturize the input devices for electronic systems, the rocker switch has been designed, which allows five different contact possibilities for a single switch which can be manipulated over a relatively small area. One such device is shown, for example, in U.S. Pat. No. 6,344,618. FIGS. 1 and 2 of the present application show a device such as described in that patent.
A case 31 is provided in a generally box shape with an open top. A cover 32 is provided which covers the open top of the case. The inner bottom surface of the case has a central stationary contact 33 and a corresponding outer stationary contact 34 arranged in the center portion thereof. Four peripheral stationary contacts 35 (only one of which is shown) are placed in the four corners of the bottom surface of the case. Terminals 40, 42, 43 and 44, as well as other terminals which are hidden from view, are connected to these six contacts to connect with an electronic device. A movable contact 45 is made of a thin resilient metal sheet and disposed so that the center is over the central contact 33 and the periphery rests on stationary contact 34. A manipulation body 46, including a shaft 46A, a flange 46B and a projection 46C rests on and is supported by the movable contact 45. The flange portion of the manipulation body is housed within the case and extends upwardly through a central hole in the cover 32. The flange 46B has a metal contact plate 47 arranged on four sides. A manipulation knob 48 is attached to the upper end of the manipulation body 46.
In operation, the manipulation knob 48 is controlled by the user and may be moved to any of five positions for actuation. If the knob is depressed directly downwardly, the contact is made between central contact 33 and outer contact 34. If the knob is tilted toward any of the four corners, the contact plate 47 will come into contact with the corresponding contact 35 to actuate that contact. Accordingly, it is possible for the user to select any of the four corner contacts or the center contact for actuation merely by manipulating the knob 48.
When similar products are used on a cell phone, the amount of space available for the various buttons and displays is very limited. In order to reuse space, many devices use soft keys for some functions. However, these keys consume display screen real estate and provide a relatively small display area. In addition, the close proximity of buttons on the small devices such as cell phones increases the susceptibility to an accidental button press. Accordingly, it is highly desirable to utilize arrangements which save space both for buttons and displays and which allow easy control of the various buttons.